The present invention relates to a transparent solid detergent composition, and more particularly, to an improvement of counter ions of fatty acid thereof.
A transparent solid detergent composition has a high-class image from the transparency and also, in case where proper quantity of dye or pigment is added, it is widely used for high-class detergent for face etc. because of its deep color tone or metallic impression.
In prior arts, the transparent solid detergent composition includes a base materials such as fatty acid soap and transparent ingredients such as glycerol sugar etc..
As for the fatty acid soap, alkali metal soaps which have sodium ion or potassium ion etc. as xe2x80x9ccounter ionsxe2x80x9d of fatty acid are known.
These fatty acid alkali metal soaps have advantages such as low cost, good foaming and creamy feeling, but also have disadvantages such as slightly large frictional solubility and a feeling of tautness after face washing. When a soap of fatty acid and weak base such as triethanolamine and lysine etc. was used, a feeling of tautness after washing was found, and no sufficient improvement was achieved.
An object of the invention is to provide a transparent solid detergent composition having improved feeling of use and resistance to frictional solubility etc.
It has been found that a transparent solid detergent composition including fatty acid soap of N-methyltaurine alkali metal salt, taurine alkali metal salt or hypotaurine alkali metal salt can improve the frictional solubility and the feeling of tautness after washing without negative influence to its transparency.
Namely, the transparent solid detergent composition according to the present invention includes; 3.5 wt % or more of at least one fatty acid salt selected from the group consisting of compounds expressed by the following general formulas (I)-(III);
Rxe2x80x94COOxe2x88x92H2 N+(CH3)xe2x80x94CH2xe2x80x94CH2xe2x80x94SO3xe2x88x92X+xe2x80x83xe2x80x83(I)
Rxe2x80x94COOxe2x88x92H2 N+xe2x80x94CH2xe2x80x94CH2xe2x80x94SO3xe2x88x92X+xe2x80x83xe2x80x83(II)
Rxe2x80x94COOxe2x88x92H2 N+xe2x80x94CH2xe2x80x94CH2xe2x80x94SO2xe2x88x92X+xe2x80x83xe2x80x83(III)
(wherein the formulas, R is a saturated or unsaturated hydrocarbon group with carbon numbers of 7xcx9c23, and X is an alkali metal or organic alkali)
sodium salt of fatty acid and/or potassium salt of fatty acid;
humectant; and
water.
It is also preferable that mole ratio of xe2x80x9cthe counter ionsxe2x80x9d of fatty acid is in following range;
It is also preferable that the total amount of the fatty acid salt is in 35-55 wt %; humectant is in 15-35 wt %; and water is in 15-25 wt % respectively in the composition.
Also, it is preferable to include polyether humectant which has polyhydric alcohol with three or more hydroxyl groups, 2-100 moles of addition polymerized propylene oxide and not greater than 50 moles of addition polymerized ethylene oxide. The amount of polyether humectant is preferably 5xcx9c50 wt % to the total humectant.
Also, it is preferable that the detergent composition be prepared by heating and dissolving a mixture of the fatty acid salt, humectant and water, and pouring the mixture into a frame, cooling and solidifying.
Furthermore, xe2x80x9ca transparent solid detergent compositionxe2x80x9d in the specification means a substantially transparent composition from which color agents such as dye, pigment are eliminated.